Chair spring



Feb. 23 1926, 1,574,087

o. H. HANSEN CHAIR SPRING Filed pril l6, 192l` f [ze INV EN "V" m 31g:

Patented Feb. 23, 1926.

OSWALD H. HANSEN, 0F PQRT ASI-INGTON, T TESCONSIN, ASSIGNR TO GAILSONMANUFACTURING COMFANY, 0F FR?? VTASHNGTQIY, VVVSCIOIIBTSCN, ACORPORATION 0F WSCONSIN. I

CHAR SLPRNG.

Application filed. April 16, i921. Serial No. 461,929. i

To all.' irl/i omy t may concern lie it known that @swarm l-l. HANSEN, acitizen ot' the United States, residing at Port lVashington, in thecounty ot' @Zaukce and State ot lllisconsin, has invented a certain newand useful Chair Spring, ot which the following is a specification.

This invention relates in general to im` proveniente in the art ofmanufacturing` and ot operating resilient restraining elements, andrelatos more specifically to improvements in the construction andmanipulation oi' helical cushioning springs for tiltable chairs and thelike.

A general object ot the inventionisto provide an improved spring`structure which is simple in construction and eliicient in operation.

lt is customary, in the construction of tiltable office chairs otdifferent types. 'to utilize helical springs of either the tension orcompression type, for the purpose ot' cushioning the backwardly Itiltingseat and to return the seat to normal position. rlhe helical tensionsprings now universally employed, are costly to manufacture because theopposite ends ot they springs are bent into loops which are pivotallyattached to the relatively tiltable chair iron members, these loopedsupporting ends frequently breaking thereby necessitating replacement otthe entire springs. lThe pivoted tension springs although costly andsubject to trequent renewal on account oi breakage, do not bendlaterally du-e to transverse angular displacement oit the pivotal endsupports, because these pivotal supports accommodate such angnlarity andalways maintain the longitudinal spring axis rectilineal. The helicalcompression springs now universally employed, are relatively inexpensiveto manufacture as they may be cut to suitable p lengths from acontinuous helical spring ot proper diameter, and no distortion of thespring ends is necessary. These compression springs when applied tochairs, are ordinarily set between cast iron sockets fastened to therelatively tiltable chair iron members, the sockets serving to retainthe springs in place and to prevent rotation ot the springs about theirlongitudinal axes. The helical compression springs are however subjectto objectionable transverse bending during the tilting and returnmovements of the seat, due to the relative transverse angulardisplacement oithe sockets with respect to the longitudinal spring axes.This transverse bending of the springs weakens the same and causes themto break, thereby also necessitating frequent spring renewal. Both ofthese prior forms or types ot helical springs also are objectionablebecause they become squeaky when n ot suiiciently lubricated, due

Vto the relatively great transverse angular displacement ot the springend supports with respect to the longitudinal spring axes, which exists'in practically all of the present commercial chair irons.

A more speciiic object of the present invention is to provide animproved compres- `sion spring' for tiltable chairs and for simitating`alteration ot these irons. A further object of the invention is to avoidnecessity of utilizing expensive cast end sockets for springs of thecompression type, by substitilting relatively inexpensive sheet metalstampings which will ellectively support the spring and which willprevent rotative displacement thereot about its longitudinal axis. Stillanother object of the invention is to provid-e a simple and convenientmethod of inserting and removing chair springs. These a-nd otherobjectsofthe invention will be apparent from the following description.

Some of the novel features of chair construction disclosed but notspecically claimed herein, form no part of the present invention andconstitute the subject matter of application Serial Number 424,015,filed November 15, 1920.

A clear conception of an embodiment of` the invention and ot theoperation ot a device constructed in accordance therewith. may be had byreferring to the drawing accompanying and forming a part of thisspecification, in which like reference charactors designate the same orsimilar parts in the various views. p I

'through the improved spring structure.

Fig. -l is an end view or the improved spring struct-ure.

F is an end view of the iront spring structure support.

rlhe t-iltable revolvino' chair disclosed iii Fig. `l, comprisesgenerally a base, a ver leal standard '-l having its 'lower extremityrigidly secured to -the base. a manually adjust'- ab'le nut le securedto the standard d, a

'bracket suppe ted upon the nut and Lnounted upon vthe upper portion otthe stand an inverted lll-shaped spreader 'i' 'lior :ally piyotallymounted upon 'the bracket l5, spider arms 3 rigidly secured to the upperside portions .ofn the spreader 7 and a seat 2 attae'hedto the lirontand rear ends of the spider arms 3. VThe 'chair base comprises iour legsextending radially a 'av Vtroni the lower e3;- treinity of thestandards7 top and bottoni plates 3l secured to the standard andengaging up and 'lower vpoi-tions oil' ythe iregs 33, and i'iller blockslocated in the corners formed by the eoacting inner leg ends. Thecei'itralvertical standard 4i.- lwhich has its low-er extremity rigidlysecured to the chair base, has "itsrupper portion screw threaded andprovided vritli'a longitudinal recess. rlhe Vnianually adjustable nutlil has a central bore provided witl. screw threads which coa/ct withthe threads on the standard 4i, and is Afurthe:provided with a `lockingpin lien'g lvble witlrtlie longitudinal recess or the sandard to lackthe iiut l-l in an adjusted 'position against movement relative to thestandard. The upper Acentral portion or -the nut l-lV is provided withan annular recess within'whieh a bearing element l5 niay be located.rThe inain bracket 5 which is freely rotatably vmounted upon the upperportion ofthe standard il, *has an elongated upright hub which is boredto receive the standard Jiand which is provided at its lower extremitywith -a flange eoacting with the 4bearing element 15. The nut le ispro-vided with one or more inwardly pi'fojeeti'ng retaining lugs 16freely iotatabl) which extend over the lower bracket iliange and preventaxial separation of the nut le and bracket 5. The bracket '5 has a for--'wardly projecting karm 6 the lower rear portion-of which is providedwith ak pair ot spaced downwardly extending' parallel lugs7 and theforward upper vextrei'nity or .l-3 which may be yriveted to theVsuppoitin-g elen'ients.

vwhich isibored to receive and to Vsupport ilireiferably made yet sheetniet-al and has itsy lower side w llls ipivotally connected to thedownwardlyY extending bracket lugs by means or a horizontal transversepivot pin spreader. 'ilio spreader .7 .oscillatory about the lpivot pinlf2-3 and transversely oi" the standard el, and has an upper abutment 22which is engageable with the bracket abutment :23 to limit the rearwardswinging movement el the spreader 'i' and sea-t2. The lower lfrontsurfaces 2l .or 'the spreader side walls are en'ageablo with 'the upperrear surfaces oifthe abutnients 25 to limit the forward swingingmovement or the spreader 'i' and seat- 2.

Vlhe spreader T and the parts associated therewith, are at all timesurged forward toward the lnacliet Yabutn'ieii'ts by means oi" .a 'pairoi' laterally spaced helical coinpression springs 8. The springs S areiden- `tical `in structure andare formed by cutting along coil ot springrod or wire vinto suitable llengths a'iidwitliout distortiiigthe ends otthe ware. rllie opposite lends ofit each spring 'S terminate adjacent toa central longitudinal yplane of the spring 8. Within each spring'- S islocated a :pair or" T-shaped .tension plates lor ineiiibers l, 19 whichare identical :in structure and which are prete ably iioriiied otslieetmetal with the aid oldies. Each ott-he '1F-,shammi iimqion inein- 'bers18, 1.9 consists of an elongated portion each tension member 18., 19upon which 'the projections 2O are torined, is also 'provided with yacentral recess 21 for permit-ting full expansion oil the spring '8without interlering with :the relatively movable spring orotrudino'yend-s ot the tension members 1S n 1 s 19 are il'n'oifided `withsuspension Vholes which Ymay be or any `desired sha-pe. The yholes oicthe forwardly projecting vtension members 19 are engaged by the endportions 28 ot the spring supporting b'loek 9, while the holes or' Atherearwardly projecting` `tension members 18 are engaged by the transversespring supporting pin l2. The block 9 is adjustably secured to theLbracket arm G by means orp an adjusting bolt l0 'having a The frontandrear square portion fitted within a square hole in the block, and anadjusting nut 11 which has screw thread coaction with the bolt therebyserving to vary the degree of compression of the springs 8. The block 9is provided with eccentric end portions 26 and cylindrical centralmedial portions 27 connected with the end portions 26 by means of theelliptical portions 28, see Figs. 2, 3 and 5. The ends of the pin 1L,are recessed at the portions 29 thereof, these recessed portions 29coacting with the spreader side walls to prevent endwise displacement ofthe pin 12, as shown in Fig. 2.

During normal use of the chair, the seat f2, spider arms 3, spreader andbracket 5 are free to be revolved about the standard it and upon thebearing element 15, without varying the height of the seat. The weightof these revoluble elements and of an occupant of the chair, issupported by the base structure through the intervening standard 4l andnut 14. The chair seat andspreader 7 may be tilted rearwardly at willuntil the upper spreader abutment 22 engagesthe npper bracket abutment23, the springs 8 being compressed during such tilting and. the members18, 19 being subjected to tensional stresses. Upon release of the seat2, after having been tilted, the springs 8 expand and srving'the`spreader 7 forwardly until the abutment surfaces 24 engage the bracketabutments In order to insure such return moven'ient of the seat 2, thesprings 8 are placed under initial compression by manipulation of theadjusting vnut 11.

If it is desired to vary the Vheight of the chair seat 2, it isnecessary to release the locking pin 17 and to rotate the adjusting nut14 relatively to the stationary standard Ll. The nut lll will thentravel along the standard l to the desired position of adjustment, whenit may be again looked to the standard by allowing the end ofthe pin 17to snap into the longitudinal recess of the standard Ll, The springs 8maybe readily remove-d by unsorewing the adjusting nut- 11, whereuponthe tension members 19' will be moved rearwardly until the pm 12 entersthe recesses 21 of these members, and the portions 2S ofi the blockQenter the recesses 21 of the tension members 1S. The springs will thenhave been entirely relaxed, and the supporting pin 12 is free to berotated 180 degrees and removed from the openings in the side walls ofthe spreader T. The tension members 19 may then be removed over theeccentric end portions 26 of the block 9 and the pin 12 be removed fromthe openings in theprotruding ends of the members 18, whereupon thetension n'iembers 18, 19 may be freely endwise removed from the springs8. lt will thus be noted that the spring adjustment and removal may bereadily accomplished.

It will also be noted that the springs 8 may be manufactured at minimumcost and that the members 18, 19 positively prevent transverse bendingof the springs 8 with respect to their longitudinal axes. rlhe springelement disclosed in Figs. 3 ande, and comprising a compression spring 8and a pair of tension members 18, 19, may be readily substituted forastandard tension spring having hooked ends.' The tension 'i7 members 18,19 may be constructed of sheet metal with the aid of dies, therebyminimiz- Y ing the cost of manufacture thereof.' The members 1S, 19besides serving ro compr-ess the springs 8. also prevent rotation of thesprings about their longitudinal axes by providing abutments for thespring wire ends.

It should be understood that itis not Vdesired to limit the invention tothe exact details of construction and of operation herein shown anddescribed, for various modifications within the scope of the claims mayoocur to i ersons skilled in the art.

't is claimed and desired to secure by Letters Patentz- 1 90 1. A springfor tilting cha-irs comprising,

a .helical compression spring having substantially' circular coils, and`a tension member engaging each end coil of said spring, each of saidmembers abutting an extreme end of said spring to prevent rotativemovement of said spring about its longitudinal axis.

A spring for tilting chairs con'iprising, a helical springl havingsubstantially circular coils, and a xl'shaped member forming a 100Vtransverse abutment for each extreme end of said spring to preventrotation of said kspring about its longitudinal axis, said membersengaging the opposite end coils of and extending longitudinally throughsaid spring in opposite directions.

3. A spring for tilting chairs comprising,

a helical spring having substantially circular coils, and a pair ofmembers engaging the opposite end coils of and extending longitudinallythrough said spring, each of said members having a transverse projectionabutting an extreme end of said spring to prevent rotation of s-aidspring about its longitudinal axis.

4. A spring fortilting chairs comprising,

a spring formed of a coiled rod having ends terminating on oppositesides of a longitudinal central plane of the spring, and a pair oftension members engaging the opposite end coils of said spring andabutting the eX- treme ends of said rod to prevent rotation of saidspring `about its longitudinal axis.

5.k ln combination, a standard, a bracket pivotally mounted upon saidstandard, a spreader pivoted to said bracket in front of said standard,a tension member'seoured to said bracket in front of said standard, aten sion member secured to said spreader in front of said standard, anda helical compression spring having its opposite end coils engaging saidmembers and its opposite ends abutting against said tension members toprevent rotative movement of said spring about its longitudinal axis.

6. A spring' for tilting chairs comprising, a. helical compressionsaring, and a tension member engaging' each endcoil ot said spring, eachof said memiers abutting an extreme end ot' said spring to preventrotative movement ot said spring about its longitudinal axis. e

7. ln combination, a standard, a bracket mounted upon said standard, aspreader pivotcd to said bracket in front of said standard, a tensionmember pivoted to said spreader in front oi said standard and verticallyabove said spreader pivot, a tension member secured to said bracket intrent or the pivot et said spreader` supported tension member, and ahelical spring embracing and compressible between said tension members.

8. ln combination, a stai'idard, a bracket mounted upon said standard,spreacer pivoted to said bracket in front ot standard, a tension memberpivoted to said bracket in front of said standard, a tension memberpivoted to said spreader in liront oi' said standard, and a. helicalcon'ipression spring embracing and compressible between said Y tensionmembers.

tative movement of said spring about its longitudinal axis.

il. In con'ibination, a. standard, a. bracket pivotallY mounted uponsaid standard, a spreader pivotally mounted upon `said bracket, a.tension member secured to said bracket, a tension member secured to saidspreader, and a helical compression spring` enibracinl and compr ssibleby both oi: said t tension nembers and havingl opposite ends abuttingagainst said members to prevent rotative. movenient ot said spring aboutits longitudinal artis. f

l2. ln combination, a standard, a bracket mounted upon said standard, aspreader mounted upon said bracket, a helical compression spring, and atension member eneach end ot said springl and extending longitudinallytherethrough, said tenA sion members being secured to said bracket andto said spreader respectively.

ln tcstimon7 whereof, the si gnature of the iniventor is ati'ixedhereto.

